Amber’s heart goes out to her. She looks so devoid of hope. ‘I’m sorry. Hopefully it won’t be too long.’

‘And then what?’

Amber wants to give her an answer. But she really doesn’t know. It’s already been made clear they can’t let Lumin stay with her.

‘We need to find this place,’ Amber says, staring at the waterfall. ‘Can I borrow the notepad they found you with? I’m going to spend the day going over this all. Consider me your own private detective.’

Lumin pulls the leather notepad from her back pocket. ‘There are some other pictures I drew in there too. Good luck, Sherlock,’ she replies with a bitter laugh. ‘There are over a hundred waterfalls in the UK. God knows how many around the world.’

‘You remembered something!’

‘The number of waterfalls in the UK, how very useful,’ Lumin says sarcastically. Then she shakes her head and turns back to the TV.

That night, Amber lays out Lumin’s drawings on her dining table. The lodge overlooking the lake. A waterfall. Then one she hasn’t seen: a bench overlooking a lake and mountains, a man and woman sitting on it. She googles ‘lakes waterfall’. The first result is a tourism website for the Lake District. Turns out there are several waterfalls in the Lake District and, as Lumin pointed out, even more around the UK. Amber looks at each one, comparing them to the photo she’d taken of Lumin’s first drawing. A few stand out so she prints them off. Then she reaches for the notepad, flicks through it and stops at a page focused on the ptarmigan. There’s a sketch of a bird soaring over a lake. She reads the note next to it: Ptarmigans are masters of adapting to their surroundings. Feathers will turn white in the winter to act as camouflage against the snow. They prefer to live high up in the mountains but will come down to intense forest areas if it gets very cold.

She flicks through the other pages then finally finds what she’s looking for: a sketch of a rowan tree, a small furry creature with pointed ears sitting beneath it. Pine martens rely heavily on rowan berries as the colder months descend. Their scats are distributed wildly and give a good indication where these elusive creatures have been.

She turns back to her laptop, looking up pine martens.

Pine martens are mostly found in the north of Britain. They prefer woodlands, climb very well and live in holes in trees. They are often known to forage in the gardens of people living in the Scottish Highlands.